Mike Graham/Gary Summers

[Floyd Staggs]

Break out the pop corn. This might get good.

[FireSale]

For everyone's info, the "D-" at the end of a Ford casting number is a revision suffix. DA is the original head. When an engineering change is made to the part the last letter of the suffix is moved down the alphabet. DC heads have had two changes made to them. They may cc the same, but something has been changed. I think that when the suffix was changed, the factory published HP rating stayed the same. NHRA decided they could document the HP of the DA head but not the others and edited the guide to recognize only the DA as legal. Very difficult to build a 1977 Ford 302 stocker.


'77 Chevy 305/145 has three head castings listed
'68 Chevy 327/350 has seven.


I have a Root Beer in the 'fridge...

[RJ Sledge]

I believe that once NHRA takes a good look at this it will be reversed. I'm sure that this has happened many times over the years with part numbers added and dropped by mistake when updating blueprint specs. Have seen it happen a lot and have seen many mistakes. Big problem is Ford had part numbers and casting/engineering numbers, common parts number for early Ford heads always had a "6049" middle number and casting/eng commor middle numbers were "6090" and I believe that is where NHRA got confused when adding or dropping head numbers. Like D70E-6090-da casting number on head could have been the D70E-6049-dc "part number". Same head just different numbers one a part number and the other a casting/engineering number cast on head.

You need to remember to not take anything for granted when it comes to changes to casting/part number addition and deletions. You need to keep an eye on the blueprint specs for your own combination(s). If you find something not right you need to notify Pat at NHRA and get it sorted out. And get it in writing. Wesley is the best at this, but don't know if he is getting involved in this or not now, but he understands Racers and the problems they can run into.

I can imagine that its an overwhelming job staying on top of this and mistakes happen quite often.

Gary and Mike good luck with the outcome.

R J Sledge

[Mark Yacavone]

Originally Posted by QuickII

I heard from a reliable source it was for altering the intake casting number,

77 is one year only, but shouldn't be hard to find.

Originally Posted by QuickII

booster modifications,

So what?

[Billy Nees]

Originally Posted by QuickII

I heard from a reliable source it was for altering the intake casting number, and booster modifications, not the head at all.

I have been told on numerous occasions by numerous Tech people (including Gracia) that NHRA Tech ONLY checks carb model,throttle bore and venturi size. Period.
If there has been a change in that policy, I'd sure like to know!

[Bob Mulry]

Originally Posted by Billy Nees

I have been told on numerous occasions by numerous Tech people (including Gracia) that NHRA Tech ONLY checks carb model,throttle bore and venturi size. Period.
If there has been a change in that policy, I'd sure like to know!

Billy,

I don't want to get pissy, BUT, so it's OK to polish the secondary bores on a Q-Jet, grind off all of the casting flash, remove he choke plate and machine off the choke horn????

CARBURETOR
Must be correct year, make, and model specified for car’s engine;
fuel or air bleed passages may be resized. Drilling idle holes in
primary
throttle blades permitted. Other modifications prohibited.
Sandblasting, grinding, flash removal, dry film coating, or any
other modification to carburetors prohibited. Replacement
carburetors permitted provided they are same model, type,
throttle bore, and venturi size. Computer carburetors use latest
model non-computer carb for engine application.

Doesn't look like it to me, but on the other hand...….

WTF do I know????

[Hacksaw]

Originally Posted by Billy Nees

I have been told on numerous occasions by numerous Tech people (including Gracia) that NHRA Tech ONLY checks carb model,throttle bore and venturi size. Period.
If there has been a change in that policy, I'd sure like to know!

You may be correct, but don't you think an official should drop the hammer if he sees a funky casting number mod? Of course. They are looking, maybe not checking.

[Billy Nees]

Originally Posted by Hacksaw

You may be correct, but don't you think an official should drop the hammer if he sees a funky casting number mod? Of course. They are looking, maybe not checking.

NHRA hasn't checked carb #s for years!

[Jeff Stout]

How about intake numbers altered or otherwise?

[Shadylane]

Originally Posted by Jeff Stout

How about intake numbers altered or otherwise?

They did on my car!